The Aug. 12 2008 announcement of IBM's XIV disk storage array is, in some ways, counter to other recent disk announcements but may foretell what some of the key disk storage ingredients for success will be in the future. By initially supporting up to 180, 1-terabyte SATA drives that spread disk volumes across all physical drives, several opportunities to simplify storage management present themselves:

There are no distinct technology tiers such as flash, high-performance disk and power-up and power-down disk to configure and manage.

All volumes are divided into 1MB partitions which are randomly distributed across all the disks and then spread across all 180 drives, reminiscent of single-level storage on the iSeries (formerly the AS/400.) This approach establishes a relative equilibrium and further simplifies many time consuming and often complex data placement and performance tuning chores, since customers simply can't influence much in this area as there aren't many knobs to turn.

XIV claims mainframe, DFSMS-like, allocation levels far beyond the typical 30-45% utilization levels for non-mainframe systems. The question of "what applications are best suited for XIV" might be better stated as "what applications are not best suited for XIV", given this automatic approach to data allocation. As a result of this, XIV may usher in the long-awaited shift from a CAPEX to OPEX customer mentality as operational overheads appear to be minimal.

Action Item: XIV represents a "no more tiers" storage solution - at a time when storage tiers are quite popular. Don't try to fit XIV into a single level of the tiered storage hierarchy. XIV is a low-touch, hands off, don’t fool with it, disk storage system. If you trust IBM to do most of the management tasks transparently, XIV may be for you. With limited resources and mounting economic pressures, potential operating cost benefits could be significant. A deeper look at the potential benefits XIV offers is warranted.

Comments on 'XIV - Simplicity and No More Tiers?'

Interesting question Bert. The problem with many tiering implementations today is they're not automated. In other words I allocate a specific group of data to a specific tier and don't touch it. I get the advantage of using higher capacity lower cost devices (for example) but if something changes I have to manually move things around. Compellent is one exception to this and there may be others. XIV is one step forward in automation/simplicity but, today anyway there's no way to tier storage so you could argue that's a half step back.